rnevius / djangoref

A cheat sheet for Django - because remembering fields, APIs, decorators, and more can be hard

Django Cheat Sheet

The goal of this in-progress repository will be to concisely capture / document common, core Django tools. Where appropriate, code samples will be added to highlight common use cases. Links to popular Stack Overflow answers will also be added to further explain topics.

Contents

Templates

• Tags
• Filters
• Date formats

Models

• Field options (kwargs)
• Fields
• Meta attributes
  • abstract
  • app_label
  • db_table
  • get_latest_by
  • managed
  • ordering
  • permissions
  • proxy
  • unique_together
  • index_together
  • verbose_name
  • verbose_name_plural
• Validators

Signals (NOTE: Perhaps nest these under their appropriate sections)

• django.db.models.signals
• django.core.signals
• etc.

Querysets

• Methods
  • all()
  • none()
  • filter(query)
  • exclude(query)
  • order_by(field...)
  • etc.
• Queries (lookups)
  • exact
  • iexact
  • contains
  • gt
  • etc.
• Aggregation functions

Forms

• Common kwargs
  • required
  • label
  • help_text
  • initial
  • validators
  • widget
  • error_messages
  • localize
• Fields
  • Boolean
  • Strings
  • Choices
  • Dates & Times
  • Numbers
  • Files
  • Internet
  • Misc
• Validators
• Views
  • Shortcuts
  • Decorators
  • GCBV
• Formsets
• Widgets
• ModelForm & ModelFormSet

Admin

• ModelAdmin
  • Options and callbacks
• InlineModelAdmin
• AdminSite

Settings

Testing

Urls

Management commands

• Migrations
• Shell
• Server
• etc.

Misc (not sure if these are staying)

• The request object
• Custom user models
• File upload example
• null vs. blank — Differences, and when to use them

Models

Model Field Options

Option	Type	Default
null	boolean	False
blank	boolean	False
choices	iterable (list or tuple)	None
db_column	string	None
db_index	boolean	False
db_tablespace	string	None
default	value or callable	NOT_PROVIDED
editable	boolean	True
error_messages	dictionary	None
help_text	string	'' (empty string)
primary_key	boolean	False
unique	boolean	False
unique_for_date	string (DateField or DateTimeField name)	None
unique_for_month	string (DateField or DateTimeField name)	None
unique_for_year	string (DateField or DateTimeField name)	None
verbose_name	string	None
validators	list	[] (empty list)

Model Fields

| Field Name | Options | Notes | |------------|------------------|----------|-|-| | AutoField | | You usually won’t need to use this directly. | | BigIntegerField | | For integers between -9223372036854775808 and 9223372036854775807 | | BinaryField | | Reminder: don't store files in the db | | BooleanField | | A true / false field. Use NullBooleanField to accept NULL values | | CharField | max_length=None | For small- to medium-sized strings | | CommaSeparatedIntegerField | max_length=None | | | DateField | [auto_now=False]
[auto_now_add=False] | | | DateTimeField | [auto_now=False]
[auto_now_add=False] | | | DecimalField | max_digits=None
decimal_places=None | Uses Python's Decimal type | | DurationField | | Modeled in Python by timedelta | | EmailField | [max_length=254] | Uses EmailValidator to validate input | | FileField | [upload_to=None]
[max_length=100] | | | FilePathField | path=None
[match=None]
[recursive=False]
[max_length=100] | | | FloatField | | Uses Python's float type | | ForeignKey | othermodel
[ondelete]
[related_name] | A many-to-one relationship. See additional arguments in the docs. | | GenericIPAddressField | [protocol='both']
[unpack_ipv4=False] | If blank=True, null must be True | | ImageField | [upload_to=None]
[height_field=None]
[width_field=None]
[max_length=100] | Requires the Pillow library | | IntegerField | | For integers between -2147483648 and 2147483647 | | ManyToManyField | othermodel
[related_name] | See additional arguments in the docs. | | NullBooleanField | | Like BooleanField, but allows NULL values by default | | OneToOneField | othermodel
[ondelete]
[parent_link=False]
[related_name] | | | PositiveIntegerField | | Like an IntegerField, but must be either positive or zero (0). | | PositiveSmallIntegerField | | A PositiveIntegerField for small values. Values from 0 to 32767 are safe in all databases. | | SlugField | [max_length=50]
[allow_unicode=False] | | | SmallIntegerField | | Integers between -32768 and 32767 are safe in all databases. | | TextField | | A large text field. max_length is not enforced at the db level. | | TimeField | [auto_now=False]
[auto_now_add=False] | Represented in Python by a datetime.time instance. | | URLField | [max_length=200] | A CharField for URLs | | UUIDField | | | |